This invention relates to a hair conditioning composition which is a mixture including water, a thickener, and an organosilicon compound which is a polyorganosiloxane; and to a hair shampoo conditioning composition in the form of a mixture including water, at least one surfactant, a thickener, and a conditioning compound. More particularly, the conditioning compound is a siloxane selected from the group consisting of carboxy functional polysiloxanes, carboxy-glycol ether functional polysiloxanes and carboxy-glycol ester functional polysiloxanes.
The term "conditioner" in relation to hair grooming preparations, refers to an ingredient for enhancing the manageability, appearance and feel of treated hair. Such materials should be capable of acting as a lubricant, reduce the resistance of wet or dry hair to combing, minimize tangling, make hair softer and smoother, improve its set retention when styled, and act as an antistatic agent, reducing or eliminating the phenomenon of `flyaway` due to the accumulation of static electricity without producing build-up on repeated application which in turn causes hair to become lank and dull. Another function of hair conditioners is to improve curl retention and to impart body and gloss to hair. Materials which are substantive to hair are more effective in this respect. Quaternary ammonium compounds, like cetyl trimethyl ammonium chloride, have been shown to be effective as conditioners at concentrations as low as 0.5%. Silicones can be used at even lower concentrations.
Hair conditioning is a surface treatment aimed at improving the condition of the hair in terms of the attributes just mentioned. It only affects the hair shaft outermost layer or the cuticle. The latter, apart from having a protective function for the layers below it, also determines the frictional properties of hair and hence its feel. It has been found that hair conditioners containing a quaternary compound or a silicone are effective in reducing damage to hair during combing and brushing by reducing friction between comb, brush and hair. This effect is improved when the lubricant is substantive to hair.
The phenomenon of "flyaway" has been corrected by the neutralization of the static charges generated by combing with a conditioning agent that lubricates the fibers. The parallel alignment of hair fibers by a material with the correct refractive index has also led to improvements in hair gloss. "Hair body" as a conditioning aspect is assessed by a subjective evaluation of the user as to the appearance and general feel of the treated hair. An increase in interfiber static friction imparts body by creating bridges between fibers. It should therefore be apparent that the conditioning function is an important aspect in hair care applications in addition to the more general requirement relating to cleanliness. Silicones are capable of providing the many conditioning benefits noted above, and offer an alternative conditioning agent to conventional organic equivalents. In certain instances, combinations of organic conditioning agents and silicone conditioning agents have been found to be advantageous.
Aminofunctional siloxanes are known in the hair care and fabric care industries as conditioners and softeners, respectively. The aminofunctional materials are applied to hair in the form of a conditioning shampoo, pre-rinse or post-rinse conditioner. Aminofunctional siloxanes are also commonly added to hair dyes and permanent wave systems for their conditioning effect. In fabric care applications, aminofunctional siloxanes are applied to fabric in the form of a fabric softener component of a laundry detergent, or as an ingredient in a rinse cycle softener. Aminofunctional siloxanes may also be applied to fabrics in a dryer by means of a dryer sheet impregnated with the softening composition.
In addition to conditioning hair and softening fabrics, another characteristic of aminofunctional siloxanes is their substantivity to hair and fabrics to which they are applied. Hair and fabrics treated with aminofunctional siloxanes are known to retain their conditioned or softened qualities through several washings.
Such aminofunctional siloxanes are shown, for example, U.S. Pat. No. 4,559,227, issued Dec. 17, 1985; and in U.S. Pat. No. 4,563,347, issued Jan. 7, 1986. The siloxanes in the '227 and '347 patents are employed as constituents in hair shampoo and hair conditioning formulations, respectively. In U.S. Pat. No. 4,866,152, issued Sept. 12, 1989, such siloxanes are employed in fabric treatment operations. While these siloxanes are known to provide acceptable levels of performance in hair and fabric treatment applications, the aminofunctional siloxanes have some disadvantages. For example, aminofunctional siloxane compounds tend to irritate the skin upon repeated exposure, and have a yellowing tendency upon application to lighter colored hair and fabric. Such siloxanes have also been known to generate an unpleasant odor which consumers find less than desirable in certain applications.
In contrast to the above, the carboxy, carboxy-glycol ether, and carboxy-glycol ester, functional polysiloxanes of the present invention suffer from none of the foregoing disadvantages of the aminofunctional siloxanes noted, and provide performance characteristics equivalent to, if not better than, the aminofunctional materials. For example, it has been shown that a single semi-occluded skin contact for twenty-four hours results in no detectable irritation. It has also been shown that lighter colored hair treated with the Materials of the present invention possess less tendency to yellow. However, neither carboxy nor carboxy-glycol ester siloxanes are new. Carboxy functional siloxanes, for example, are disclosed in U.S. Pat. No. 4,271,215, issued June 2, 1981; U.S. Pat. No. 4,477,514, issued Oct. 16, 1984; U.S. Pat. No.. 4,744,978, issued May 17, 1988; and in U.S. Pat. No. 4,857,212, issued Aug. 15, 1989. Carboxy-glycol ester functional siloxanes on the other hand are taught, for example, in U.S. Pat. No. 4,366,001, issued Dec. 28, 1982; and in U.S. Pat. No. 4,587,320, issued May 6, 1986. However, none of the foregoing patents are specific to hair conditioning applications of the carboxy and carboxy-glycol ester functional polysiloxanes, nor do they teach one skilled in the art how to produce specific conditioning formulations for successfully applying such siloxanes to the hair.